Clipping machine



sept. 14, 1942..4 G. MAURER CLIPPING MACHINE Filed April 1, 1942 5 Sheets-Sheet l n 1 1 1 l I I I I I l I I) sep1. 14, 1943. G. MAQR'ER 2,329,549

CLIPPING MACHINE Filed Apri1 1, 1942 5 sheets-sheet 2` 5 Sheets-SheerI 5 G. MAURER CLIPPING MACHINE Filed April l, 19.42

Sept. 14, 1943.

sept. 14, 1943. G. MAURE.

` CLIPPING MACHINE Filed April 1, 1942 5 Sheets-Sheet 4 Sept. 14, 1943. G. vMAuRl-:R 2,329,549

CLIPPING MACHINE Filed April l, 1942 5 Sheets-Sheet 5 Patente-d Sept. 14, 1943 vGottfried Maurer, Zurich, Switzerland, assigncr to A. Mller & Cie,` Maschinenfabrik und Eisengiesserei, Ak tiengeserllschaft,y Brugg, Switzerland, a joint-stock company-of Switzerland Application-'April 1, 194,2,"seria1 310.4131291 In Switzerland February 27,' 1941 f v 5 claims.' (el. 1642-1-54.)

The object of the present invention is'a clipping machine, specially but not exclusively. for cutting veneers. f

u The clipping machines used up till now for cutting non-metals, specially wood, as, e. g. the wellf known lveneer clippers, had but one movable knife. Pressing the chamfer 0f this knife into theworkpiece caused, at the end of the cutting process, a tearing out of material from that portion of Athe work piece lying at the side ofthe cutting surface of the knife. Hence, the cutswere not clean, which was specially annoying -in the case-of veneers. Y

l The 'clipping machine according to the invenu tion remedies these inconveniences. -terised in that it comprises .a main knife andan auxiliary knife. v l "l s .f f Inthis machine the auxiliary knife, towards rtheie'ndof the cutting. process, has already cut theiworkpiece before the charnfer cf the main knife hadthe opportunity to tear out material from. the vportio-nfof `the work piece lying-at the -sidefofthecutting'surface of the knives. In this way, the cut becomes very clean. j-Ina preferred embodiment the knives are mov- :3.,5bly-arrjangedV in such away that they carry out Va4 drawing, cutting movement. I Thetwo knives lying opposite each other are preferably driven It is characb-y acomrnon member. In this way, a mutual position ofthe paths-of the Atwo knives is obtained, which always remains exactly the same. -Furthe'rmore, `clashing together of the two knives is avoided. H f

winitne clipping maehineaccording to thelnvention the. work pieces may be Leut satisfactorily evenrin the'direction of libre 'without running therisk of being split, because the cut of the work piecemade by the auxiliaryvknife prevents any splitting effect of the main knife. il' l Other objects andfeatures will be apparent as the-following description'proceeds, reference be- 'ing-had-to the accompanying drawings in which Figs.I 4la and lb are a front'view from the sideopposite-to the clipper knives. f

FigsjZqL and 2b area planA View of the machine, 5

Fig 3 is an enlarged section along the line Fig. .4 Yis an I enlarged iv'v--ivv if-rig. 1,VV Figi. 5 shows adetail sure beam, l 4 11 Figlfi visa section along the line VI--VIl of Fig. 'I is a fro-nt view of the disengaging clutch ofthe drive for the clipper knives, l

section along'jthe line of thedrive for rthe presya section along the line VIII-VIII of f'Fig. 9 shows theI position of the clutch pin when the crankshaft is engaged,

-Figlll 'illustrates in a schematic lway the courseof the curves run through by the two clipper-knives.

I Fig. il shows" a pecularity in theniutual position= of the clipper knives'.v

The upperl knife I forming the main knife, and the lower knife 2 lying opposite the knife I and forming the auxiliary'knife are fixed to the movable knife holdersf. lll respectively. The main knifeV I-is fixed to lthe holder 3 with its cutting vedge preferably ascending from left to right in Figsnldr and lb. 'These holders are guided in the frame parts 5 and 6, viz.: the knife holder 3 by the surfaces 85,86 (Figs. Zdand 2b) and the holder 4 by the 'surfaces 81,88 (Fig. 4). The

`upper knife holder 3 is pivotally suspendedl on the frame parts 5 and S by means c f the links 'l and the bolts 3 and S, while the lower knife holder lv-is carried by the levers I I and I2 by ineanslofthe'boltgy IB. These levers are pivotally as working surfaces for a. wrench for the pur-v pose of turning the eccentric pin. By suchturning the position of the levers I I, I2 and thus the position of the auxiliary knife 2 `can be changed, whereby the depth of the cut of the lower knife than. be adjusted. v Motion is imparted to the knife holders 3v and 4 by the lever I5 through the rods IIS, Il. vlhese rods are pivotally fixed to the lever I5 by means of thebolts I8 and IB respectively, 'and to the holder 3 vand lever I I by means of the bolts 2Q and 2| respectively. The lever I5 is rotatably mounted on the bearings 23, 24 of the frame parl-,5 by means of rthe pivot 22 (Fig. 3). The lever I5fis driven by the crankshaft 25 --(Fig. S) and by the crank rod 28 connecting the crank pin 26 with the bolt 21' of the lever I5. The dis- 'engageable drive of thecrankshaft 25 will be described later on. fr

In the frame parts 5 and 6 the pressure beam 29 is also guidedand that by the surfaces 89, 90 (Figs. 2a and 2b). It serves the purpose yof lpressing the work piece-to be cut,'e. g. a veneer, towards the table 30 (Fig. 4) and of holding it fast while cutting. This pressure beam 29 is carried by the rods y3| pivotally connected -With the pressure-beam by means of bolts 32 and with the bent levers 34,- 35 respe`ctively by means of @the bolts 33.'- TheHbent-lcver 34 is mounted/on the bearings 31, 38 of the frame part 5 by means of the shaft 36 (Figs. 3, 4). Besides, it carries a roller 39 by means of a lbolt 4I, said roller cooperating With a cam disc 40 attached to the crankshaft 25, as may specially be seen in Fig. 6. The bent lever 35 is operated by the bent lever 34 with the aid of the rod 42 which is pivotally connected with thebent levers by bolts. This rod comprises two parts coupled with each other by a sleeve 43 having rightand left-handed threads. By turning the sleeve 43 the mutual position. of the bent levers 34 and 35 can be adjusted. The rod 42 is surrounded by a spring 44 which, `at the one end, bears against a disc 45 vfixed to the rod and, at the other end against ya sleeve 41 adjustable by a nut 46. By turning the nut 46 on the thread 48 of the rod, the tension of the spring 44 pressing the roller 39 against the cam disc 40 may be changed. The tube 49 serves the purpose of protecting the spring 44 on the outside. Referring to Figs. and 6, `the pawl 5I) cooperating with the disc 5I mounted on the crankshaft 25 and being loosely positioned on the bolt 52 xed to the frame part 5, prevents the disengaged crankshaft from revolving back in 'a clockwise direction under the influence of the spring 44, in that the pawl 59 blocks the disc 5|-, VFor this purpose a torsion spring 53 constantly presses the pawl 50 against the disc 5|. At the one endthis torsion spring is fixed to a disc `54 of the bolt- 52 and, at the other end, to the lpawl 50 itself.

The disengageable drive of the crankshaft 25 will rnew lbe described as follows (Figs. 3, '1, 8)

The crankshaft 25-runs on the ball bearings A55,

,55 mounted onthe frame part 5. Bushings 51 and 58 are-keyed on the crankshaft 25. On these bushings the hub 59 of the worm wheel rim 69 engaging the driving worm 6| is loosely placed. The latter is driven by a non-illustrated prime mover and by a cone belt drive through a belt pulley 62 (Figs. la and 2a). Loosely lon the crankshaft 25, but keyed on the hub 59 is a driving sleeve 53 of the pin clutch described as follows: The bushings 51 and 58 and the crankshaft 25 have a common bore 64 with its axis parallel to the crankshaft 25. The .driving sleeve 63 has three grooves 35, whose radius is equal to that of the bore 64 and which at each revolution .of the idly running sleeve 63, are once in line with the bore 84. A rotatable pin 66 is place-d in the bore -64 with running fit. This pin, within reach of the bushings 51, 58, is cylindrical, within reach of the driving sleeve G3, however, it has the hatched .cross section 61 (Fig. '1). A p awl 68 is fixed to the pin 66 and is under the influence of a spring 69 fixed to it and to a flange of the bushing, 518-. The pawl 58 may be operated by means of the lever 1I pivotally mounted. on the clutch casing 13, a spring 12 fixed to the casing acting on said lever 1I. A rod 13, operated either by hand or automatically, cooperates with the lever 1|.

This pin clutch works as follows:

The driving sleeve 63, seen in Fig. 7, rotates in an anticlockwise direction. As long as the pawl 6.8 is held by the lever 1I in the position Vshown in Fig. '7, the portion of the pin 66 having the hatched cross section 61, is entirely in line with the bore 64 of the crankshaftk 25, i. e., it does not enter any of the grooves 65 of the driving sleeve 63. This, however, meansthat .the sleeve 63- rotates idly, that the crankshaft 25 is, therefore, at rest. If the rod 13 is not dra-Wn downwards in any way, e. g. by hand or b-y an automatic control mechanism., the lever 1| is swung out of reach of the pawl 68. As long as none of the grooves 65 of the rotating driving sleeve 63 are within reach of the pin 66, the pawl 68, though released by the lever 13, remains in the position shown in Fig. 7. However, as soon as one of the grooves 65 is within reach of the pin 66, the pawl 68 and,vwith it, the pin 66 are turned in an anticlockwise direction, until the lpawl 68 strikes against the stopping surface 14.

Then the pin portion with the cross section 61 takes the position shown in Fig. 9. Now this portion has entered one of the grooves 65 of the 4driving sleeve 63 and, together with the crankshaft 2i5 and the bushings 51, 53, is now taken along. The crankshaft 25 rotates as long as the lever- 1I is not returned into the position shown vin Fig. 7. If the lever 1| is released, be it by disengaging the notch 15 of the rod 13 from lever 1I or by lifting the rod 13, the spring 12 draws, the lever 1I back into the position shown in'Fig. f1. Now the pawl 58, on its rotation, will Istrike against this lever '5I and will be returned into the position shown in Fig. '1. Now the crankshaft 25 is again disengaged. In order to prevent the disengaged parts from moving on .temporarily owing to the inertness of the moving parts, the crank disc 16 (Fig. 3) is formed as the 4bra-ke disc vof a band brake, around which the brake band 11 is laid, which, at its two ends, is screwed to the frame part 5, the one screw 18 (Fig, la) serving as adjusting screw for the band tension which must be so great that the brake stops the disengaged parts at once. It is understood that any other suitable clutch can be used instead vof va pin clutch.

The manner of action of the illustrated ping machine is as follows:

supposing that the knife holders 3 and 4 and the pressure beam 29 and their drives are in the position shown in the drawings, i. e. the knives I and 2 are open. The work piece to be cut, e. g. a veneer, may be brought between the knives on the table 30. Now the pawl 68 is released by means of the rod 13 and the lever 1I. The pin Clip- -66 engages the nearest groove 65 and the crankof the disc 40. At B the roller has reached the smallest radius of the cam disc. The lever 34 has brought the rods 3| and thereby the pressure beam 29 into the lowest position. Now, the pressure beam presses the veneer against the table 3U so that it is xed for cutting. In the time within which the crankshaft 25 has thus revolvedvby the angle a, the crank pin 26 has passed from its position a at the right of the upper dead centre into the position b at the left of the upper dead centre. The lever I5 driven bythe crank rod 28 thus remains practically in the same position. Thus the twoknives I and 2 have not yet approached each other. Not till now, when the crank pin 26 moves from b to the lower dead centre, the crank rod 28 drives the lever I5 in an anticlockwise direction. The rod I6 draws the upper knife holder 3 to the left whereby the individual points of the cutting edge of the main knife I describe arcs whose radius is equal to the length of the links 1 between they axesof the bolts 8 and 9. At the same time the rod I1 swings the lever I I in an anticlockwise direction. Each point of the cutting edge of the auxiliary knife 2 describes thereby an arc Whose radius is equal to the distance of the bolts III and I4 of the lever II from each other.

The mechanism transmitting the movement of the crank pin 26 to the knife holders is chosen f so that the mutual position of the paths of the upper and lower cutting edges is approximately ity.. As theinclination of the upper knife is but slight with regard to the knife length, it is not.

visible in the drawing.

New is also. the fact that the knives do not turn thechamfered side but the` cutting surface side towards the knife holders.

that illustrated in Fig. l0. Fig. l merely. serves the purpose of showing the ymanner, of action of the knives. Therefore, it is purely schematic and is not in exact relationfto the size of the machine illustrated. 'I9 is the path of the'cutting edge of the main knife I and 8B that of the auxiliary knife 2. BI designates the work pieceto be cut,

lying on the table 3Q. Thev points EC and D are the initial positions of the knives, i. e. the posi` tions illustrated in Figs. ld., lband 4. When the crank pin 26 now movesfrom b to the lower dead centre (Fig. la.) it is, at first, the auxiliary knife which comes into contact with the work piece,

and that in point E. It cuts the work piece from a below in drawing movement from right to left to the point F; from this point onwards it moves downward' up to the pointG and out of the work piece. The main knifehonly comes `into contact with the work piece at point H, that is, only when the auxiliary knife 2 has already left the work piece. From I-I it runs on up to the dead centre J and, in this period, cuts the work piece 8| entirely through in a drawing'movement from right to left in Figs. la, 1b. It is understood that the paths of the knives must not intersect each other,

otherwise the knives would-clash. When the crank pin 26 moves from the lower dead centre.

upwards, the knives run back along their paths 79, E@ into lthe .positions C and D. The pressure fer 82' ofthe .knife I can no longer tear'out material from` the work piece at the lower'surface,

because the auxiliary cut made by the lower knife 2 prevents this. The cutting edges of the two knives I and 2 must not liein exactly the same vertical plane, the edge ofthe upper knife-may,

seen in Fig. 4, .be displaced somewhat to the left4 with regard to the lower edge, as is indicated in Fig. 11. I-Iere too, tearing out material from the lower side ofthe Work piecer is impossible, as the upper knife, from point 83 on, has only to cut off the narrow prominence 84. This fact y facilitates the assemblage. vNocare need be taken that the cutting edges are in the'same vertical plane, but it is only necessary to see that the upper cutting edge, seen in Fig. 4, does lnot lie on the right side of the lower one. With the machine shown, work pieces may be cut-satisfactorily even in the directionof `iibre, because the lower knife first cutting the work piece, ar

splitting effect of the upper knife is impossible. As the upper knife is fixed to its holder ascending from left to right (Figs. la and 1b) cutting does not take place simultaneously over the Whole knife length, which increases the cutting capac- The clipping machine, besides Wood, may also cut other non-metals.

The main knife I might also be arranged at the bottom and the Vauxiliary knife 2 at the top.

What I claim is:

1. In a clipping machine,l a main knife, an auxiliary knife, a frame, a rst holder carrying `said main knife, swingingly mounted .on said frame,.a second holder carrying said auxiliary knife, swingingly mounted on said frame, a common member to swing said first holder and said second holder, and a crank drive to drive said common member.

2. In -a clipping machine, a main knife, an auxiliary knife, a frame, a first holder carrying said main knife, lswingingly mounted on said frame, a second holder carrying said auxiliary knife7 swingingly mounted on said frame, a com- -mon member` to swing said first holder and said second holder, a base, a pressure beam adapted to press a workpiece againstsaidr base, and a crank drive comprising a shaft and a cam disc mounted on said shaft to contr-ol said pressure beam.

3. In a clipping machine, a main knife, anl -auxiliary knife, a frame, a first holderV carrying v said main knife, movably mounted on said frame,

- said main knife and arranged in said frame, a

a second holder carrying said auxiliary knife,

' movably mounted on said frame, a drive mechanism to drive said holders, a clutch to 'control said drive mechanism, comprising a drivingpart, a driven part, and a pin revolvably mounted on said driven part and adapted, by rotation, to be lbrought in and out-v of engagement'with said driving part.

4, In a, clipping machine, a main knife, an auxiliary knife, a frame, a first Vholder carrying second holder carrying said'auxiliary knife and arranged in said frame, means mounting the vsecond holder and the related auxiliary knife to swing in an arc atfone side of the work piece to penetrate a part only of the width of the latter and tol leave the work piece'at thesame side, means mounting the first holder and the related main knife to swing in an arc to penetrate the whole width of the work piece, and means for driving the knives in timed jrelation whereby the Work penetrating movement of the auxiliary knife precedes `the pentrating movement ofthe main knife.

5. In a clipping machine, a main knife, an auxiliary knife, a frame, a first holder carrying said main knife and arranged in said frame, a second holder carrying said auxiliary knife and arranged in said frame, means mounting4 the second. holder and the related auxiliary knife to swing in an arc at one side of the Work piece 

